Spray application of coating compositions



March 2 1926. 1,575,152 v 5 c. DI BATTISTA v SPRAY APPLICATION OF COATING COMPOSITIONS Filed May 22, 19 25 INVENTOR ATTORN EY5 enemas n1 emu-Isms, or IBERWICK, rmmsnvmm smiav arrmearion or oonnye coiarosxrions.

Application filed Ila 22,.'192$. Serial N'o. 32,085;

To all whom it'may concem:

Be it known that I, CHARLES DI Ba'r'rIsTA, a citizen of the United States, residing at Berwick, in the county of Columbia, State of Pennsylvania, have invented certain new and useful Improvements SprayApplication of; Coating Compositions; andzl do' hereby declare the following to'be a full, clear, and exact description of invention, such as will enable :others skilled inthe art to which it appertain's to make and use the same. 1

- Thisinvention relates-to improvements, in

osi-

the spray application ofcoating com tions andtholi ke, and relatesparticu arly .p

to the ,Spray; application of such compositions which are solid or semi-solid or insuf-- ficiently'fluid at ordinary temperatures for,

. application inthis manner.

lordinary types. of paints, varnishes and enamels. by spray1ng. Many bituminous,.

I has hitherto been proposed to apply the "resinous and asphaltic compositions, and

a, however, are .diflicult to handle in this i way because they are insufliciently fluid except 'at--' elevated temperatures. Attempts .havebeen'made to melt and then spray such "materials while still molten, but usually they 'havebeen'found to cool too quickly and subseque y toycongeal t quickly to make thisfsatisfactory. For commercial purposes it. is usually desirableto melt such materials in batches larger than could conveniently be moved around any great number of times by a workman and this .has mvolved'the provision of some flexible connection between the supplyreceptacle containing the molten material and the spraying nozzle in order to give the workman suflicient freedom. One isadvantage of the attempts to which reference has justbeen made has been that this v it :reached the :nozzle. Choking or clogging ofthe apparatus due to delays or lnterrupflexible-connection had to be made very short inorder to prevent choking and clogging due to congealing of the molten material before tion ofthework-have also made constant attention'necessary .to keep the apparatus in operation. l-Thee economies and advantages of the.spray:'method of application diminish rapidlyzoridisappear where such factors interfere .Wltllathe continuity of operation and inhibitsthe facilityof the workman. Likewise, inmany cases, the result of the operation is unsatisfactory if the temperature falls too much before the material is actually sprayed. There have also been proposals to overcome thislast mentioned difiiculty by the apphcation of heat in the nozzle itself but these proposals of course do not relate to the problem F of uninterruptedly supplying the nozzle with the material to e sprayed through a sujficient length of flexible'connectlon togive the workman the desired freedom. It is necessary for the material to reach'the nozzle itself before such proposals can become useful. I

which is not cumbersome and which does not v I substantially differ in so far as case of opcompositionscontaimng sulphur, for exam eration is concerned from the apparatus orchnanly employed for the spray application of the ordinarytypes of paints, varnishes and enamels.

- ,According to the present invention, the

spray nozzle and the supply receptacle are connected by a flexible hose and the'material flowing through the hose is heated therein by heat generated along the length of the hose and immediately in the zone of application. As the" heating may be applied thro'u hout as much of the length of the hose as is esired, the hose also may be made as long as is desired without danger of choking The invention will be further described in i connection with the accompanying drawing which illustrates in adiagrammatic manner an apparatus embodying theinvention and adapted for operation in accordance with the invention. It will be understood, however, that this more detailed description and illustration are for the purpose of exemplification and that the invention is not limited thereto. a

metal hose adjacent the supply receptacle and another connecting clamp .,,5 is arranged on the other end of the metal hose near the spray nozzle and from these connecting clamps electrical connections 6 are provided to any suitable source of electrical power. When current is supplied to the power connections 6, it flows through the metal of the flexible hose itself as part of the electrical circuit and due to'the resistance of the metal of the hose heat is generated throughout the length of the hose through which current 'is flowing. Any material flowing-through the hose may thus be heated or ma ntained at a uniform temperature by the heat sup hed electrically throughout the length 0 the hose connecting the spray nozzle with the supply receptacle- This heating, may be easily regulated by controlling the potential at which the current is supplied with refer ence to the length and reslstance of the particular hose employed. The hose may be of steel or of bronze or. of other suitable metal. Flexible steel hose of usual con- 'struction is of appropriateresistance for the economical use of current. Other metals may be employed where the requirements as to the amount of heat to be supplied or the temperature to be used vary. t

The supply receptacle illustrated. comprises an 1nner vessel 7 v arranged within an outer vessel 8, the inner vessel extendlng to the bottom of the receptacle. The material to. be sprayed is supplied to the inner vessel through the removable cover 9 and is then forced to the spray nozzle through the connecting hose- 3 and the outlet pipe '10 which ,extends almost to the bottom, of the inner vessel by means of air pressure. exerted through connection 11. A clean-out plug 12 is provided at the upper end of pipe 10. The: air for forcing the material from the container through the connecting pi hose tothe spray nozzle is advantageous y supplied as illustrated through the jacket about the inner vessel so that it is heated approxi- 1 mately to the temperature of the material in the supply receptacle before being brought in contact therewith. Air for this purpose is supplied through connection 13 and control valve 1* to the upper part of the jacket and escapes from: the lower part of the jacket through pipe 15 leading tot-he connection steam or some other-appropriate gas mayb employ tacleat elevated teniperfiture is not desired."

receptacle in a molten condition or it may I be melted therein by the. application of heat to the lower receptacle;

In operation of the a batch of the materialto be sprayed is in-.

tro'duc ed into the supply receptacle and unless suflicientl'y fluid as introduced is brought to the required degree of fluidity therein, fi

and then while current is supplied to the electrical power connections 6 the valve 14 is opened and the material in the supply re-f ceptacle is forced out through the heated flexible hose 3 to the spray nozzle. -The op- 1 eration may be further illustrated by the fol-f lowing example: A- spray tank of 18 gallons capacity was employed in conjunction with a standard spray nozzle connected by 15 feet of standard flexible steel ho'se part or bottom of the" supply.

apparatus illustrated,

weighing approximately 0.40 pounds per foot. .The supply receptacle was kept at a temperature in the neighborhood of 300t0 350 F. by means of a burner or electrical resistance'element and thehose was kept at a. temperature between about 250 and-275; F. by current supplied to the ends of-the hose at a potential between about 18, to 2 0 volts- The current flowing was about 56 amperes. .This apparatus operated inthis f manner was femployed'for'spraying a compound in which molten sulphur v was. the

carrying agent, the com ound also includling various finelydivide materials such as powdered asbestos, and the like.

example is given simply byway of illustra- It will be appreciated that the foregoing heating effect in the hose is proportional to the square of the current and the current through any given hoseis proportional'to the applied potential." The heating within" the hose and the temperature there maintained may be increased or decreased by increasing or decreasing the potential at which the current is supplied. With *difierent lengths of hose the resistance of the hose of course varies and the potential at which.

current is supplied is correspondingly-adjusted to secureth'e desired heating efi'ect;

The resistance of di ferent materialsalso varies and here again where the hose is constructed of other conducting material the otential at which current is su plied will be correspondingly adjusted. .Di er'ent temperatures may likewise be employed with different materials and in difi'erent operations.

The connecting hose may also include one or throughout as great a length of connecting more sectionsof .rigid'piping', and may be made up, wholly or partly, of jointed or articulated piping. v

Different materials have ditl'erent characteristics as to the relation between fluidity and temperature, and, with materials that tend to congeal very rapidly or at relatively high temperatures, provision maybe made to maintain at high temperature throughout their entire length the connec-- ,tions between the supply receptacle and the spray nozzle. Most metals have a high-heat conductivity, and when using metal parts as in the apparatus illustrated a, certain" amount of; heat is conveyed through themetal of the connections to parts of the conv nections beyond the portion through which current is actually flowing. The electrical connection 5, for example, may be moved.

closer to the nozzle 2, or the power connection may be made to the nozzle itself. Similarly, the other power a connection may be made at Al instead of at o prevent temperature drop through the connection 10 to the'hose 3, or it may even be made to the metal of the supplyreceptacle itself.

It will be apparent from the foregoing de-. scription that the invention-provides an apev paratus for heating or maintaining the temperature of the material to be 1 sprayed hose as may be desired which is "110 more cumbersome than the ordinary spraying apparatus, the only additional element movable with the hose being the electrical connection adjacent the spray nozzle. vBy employlng for this connection a flexible cable thereis but very slight increase inthe bulk and weight of that part of the apparatus which the workmanhas to handle. By generating heat along the hose or in the hose itself the use of extraneous heating means or of any cumbersome connections through extraneous heating means is avoided and the heat is usefully applied as it is -enerated. Cloggingis prevented, event ou h;

7 there be accidental interruption orlong elay of the operation as the heat generated in the hose .or flezgible connectionmaintains the material therein fluid whether it is flowing or not. .The invention has been particularly described. in connection with the use of mater als necessary to be-maintained at elevated temperatures to be sufficiently fluid for spraying. .application, but the invention is also useful in other cases where it is necessary or desirable to maintain the temperature or to heat the material supplied to the spray nozzle. In cases where it is not necessary to heat the material to be sprayed nozzle.

in order itorender it sufliciently fluid for T spray application, the supply; receptacle may be unheated and the entire heat input may'be' effected-in the flexible hose connecting the: supply receptacle and the spray I claim: "I I.

- 1. An improved spraying apparatus comprising ,a'spr'ay nozzle with a supplyrecelptacle, a flexible metal hose connecting t e circuit forheating the flexible metal hose nozzle to the receptacle and an electrical substantially throughout its length, said metal hose forming. one portion of the heating, circuit, whereby material passed through-the hose from the supply receptacle will be maintained in a heated condition.

2.. In spraying apparatus, a spray nozzle and a flexiblehoSe connected thereto for supplying the f nozzle, said hose being of metal and forming a resistance element in an electrical circuit for heating material flowing therethrough to the nozzle.

- In" spraying apparatus, a spray nozzle and a hose connected thereto for supplying the-nozzle, said hose being flexible and provided with electrical heating means extend ingover afsubstantial portion of its length for heating material flowing through the "hose to the nozzle.

'4. Animproved spraying apparatus, comprising aspray nozzle and a supply receptacle, a flexible metal hose connecting the nozzle and'the' receptacle, an electrical connection'to the hose adjacent the receptacle "thej.material, ;1"ne ans for-heating the mate rial-whilezin' the container, afiexible con-' duit, havingapdischargeoutlet, through whic'hthe materialisadapted to flow means for generating-.heat'and for supplying the no .stantiallythroughout its length in order to v heatito thmmaterial in the conduit submaintain the material in a fluid condition while fiowing-therethrough, andmeans for causing the heatedmaterial to pass out of the discharge outlet ,so that it may be sprayed-upon a surface.

.In testimony; whereof I 'afiix my signature.

' CHARLES n1 BATTISTA.. 

